Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/514

420 presupposes that every collection of fossils found in a cave or river-deposit is likely to furnish a complete set of the animals living in the country at the time. The den of an Hyæna could hardly be expected to afford the same animals as those which are found in river-deposits; and the abode of a Cave-bear would most certainly contain a different suite of remains. If indeed the present distribution of animals be any clue to that of the Pleistocene, the very diversity which M. Lartet insists upon as representing different periods of time must necessarily have resulted from the same country being occupied by different animals at the same time. The Bear and Hyæna were living in the caves at the same time that the neighbouring river-valleys were occupied by the Mammoth, the Reindeer, and the Aurochs. Nor indeed does the classification apply even to the few cases on which the generalization is based. That of Aurignac, for instance, is referred to the period of the Cave-bear, although the Reindeer, Mammoth, and Aurochs are also present. The caves of the Dordogne, which have furnished such wonderful traces of the civilization of the hunter during those ancient times, are considered to belong to the Reindeer age, although the Mammoth has been found in no less than four out of the same series. A study of the distribution of these animals through the caves of France, Britain, and Germany has convinced me that three out of the four are worthless for the purpose of classification, since in the great majority of cases the four animals are associated together in the caves, and very generally also three out of the four in the river- deposits. And although the evidence seems pretty clear that the Reindeer arrived in Europe after these three animals, it competed with them for a very long time in the same area. As, also, the arctic climate gradually became temperate, it ought, à priori, to have been the first to retreat northwards, leaving the three others behind—the Aurochs to survive in the forests of Lithuania, and the other two to become extinct. We have no proof as to which of these became extinct first. The climatal change which was sufficient to banish the Reindeer from the south of France and from Central Germany had certainly not taken place during the latest stage of the Pleistocene; and the occurrence of that animal in the peat under the alluvium of the Thames, at Crossness, proves that it lived as far south as Kent in the Prehistoric age. In all probability, during some part of the vast interval which exists between the Pleistocene and the Prehistoric periods, it had become extinct in Central and Southern Europe, since it has not been discovered in any deposits in those regions which can be referred to the latter period. For these reasons M. Lartet's generalizations seem to me to be untenable, although it be true that the Cave-bear, Mammoth, and Aurochs arrived in Europe before the Reindeer, and the last-named animal departed from France and Germany before the Aurochs.